Antibodies have which structural composition?

Antibodies are proteins produced by the immune system to identify and neutralize pathogens such as bacteria and viruses. The correct structural composition of antibodies involves two heavy chains and two light chains. This arrangement contributes to the Y-shaped structure that characterizes antibodies, where the heavy chains form the main body of the Y, and the light chains are attached to each of the arms of the Y.

This specific composition allows antibodies to have a unique region known as the variable region, which is crucial for binding to antigens. Each antibody's variable region can differ, enabling the immune system to recognize a wide variety of different antigens. The stability of the antibody structure is due to interactions between these chains, including disulfide bonds, which help maintain its function in the immune response.

In summary, the presence of two heavy chains and two light chains is essential for the antibody's ability to perform its role in immunity effectively.